This project requires accessing 2371 samples from the Collaborative Perinatal Project that have been stored at the repository at -20C. Given the non-optimal storage conditions and extreme age of the specimens it has been our experience that many of these samples are desiccated or evaporated to the degree that the required 3 ml serum is not attainable. Our last project using these samples we found 4% of the original samples requested were unavailable. The repository has noted that in some case this could be up to 40%. Thus, we are providing resources for the repository to pull an additional 25% specimens to cover the costs of repeated pulls to satisfy this request. This study will link data from 52,966 children born to participants in the United States Collaborative Perinatal Project (CPP) between 1959 ? 1966 to the National Death Index, determine their vital status through 2013, and investigate the prenatal, socioeconomic, behavioral, cognitive, and neurologic risks for completed suicide. We will conduct a nested case-control study to investigate the contributions of gestational immune activity to fetal origins of suicide. The DIPHR has identified 2371 serum specimens in the NICHD-DIPHR repository from CPP participants from which we will compare levels of immune system biomarkers between offspring who died by suicide and a matched group of non-suicide controls. We hypothesize biomarker concentrations consistent with a perturbation of the maternal immune system.